Air-pump



H. L. FROST.

AIR PUMP.

APPLiCATION FILED MAR, 6, 1919.

1,362,485, Patented Dec. 14, 1920.

2 SHEETS SHEET I.

' lNVf ENTOR WITNESSES ATTORN EY H. L. FROST. AIR PUMP.

APPLICATION FILED MAR; 6.1919- Patented Dec. 14, m9.

2 SHEETS-SHEET 2.

INVENTOR r1. flan;

WITNESSES ATTOR N EY UNITED STATES HORACE LEE FROST, 0F ELIZABETHTON, TENNESSEE.

AIRr-PUMP.

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especially when approaching the fully inflated condition, may be pumped with little Y A the force exerted upon the air being pumped becoming more efficient as the resistance to the travel of the pump piston increases.

The'invention will be bestrunderstood from a consideration of the following detailed description taken in connection with the accompanying drawings forming part of this specification, with the understanding, however, that the invention is not confined to any strict conformity with the showing of the drawings, but may be changed and modified so long as such changes and modifications mark no material departure from the salient features of the invention as expressed in the appended claim.

In the drawings Figure 1 is an elevation, with parts shown in section, of a pump constructed in accordance with the invention.

Fig. 2 is a similar view but showing a different phase of the operation of the pump from that shown in Fig. 1.

Fig. 3 is a section on the line 3-3 of Fig. 1.

Fig. 4 is a section on the line 1-4 of Fig. 1.

Referring to the drawings, there is shown a main or supporting frame comprising a base plate 1 and rods 2 rising from the base plate and approaching and joined at a high point and there formed into a hub 3. Extending through the hub is a pivot screw or stud 1 on which is pivoted or fulcrumed a. hand lever 5 of appropriate length and provided at the upper end with a handle 6 by means of which the hand lever may be manipulated. The lever 5 is so mounted as Application filed. March 6, 1919'.

Specification of Letters Patent. Patented D 14 1920 Serial N 0. 280,962.

to be capable of oscillation over the base 1 about the pivot support 4.

The lever 5 has a short end 7 entering a socket 8 in a head 9, being secured in the socket by a stud 10 or in any other suitable manner. The head 9 is provided with cars 11 between which are located the outer ends of piston rods 12, of which there are two in'the structure shown in the drawings. A pin 13 serves as a pivot connection between the ears 11 and the piston rods 12.

The base 1 is provided at opposite ends with bearing blocks 14 receiving ears 15 each on one end of a cylinder 16. There are two cylinders 16 in the pump and as the pumps are alike adescription of one will apply to both. The construction of the cylinders 16 may follow the usual cylinder construction for pumps and needs no special description. Each cylinder is pivotally mounted in the block 14 at one end of the cylinder, while the piston rod 12 enters the'cylinder through the head at the other end thereof and within each cylinder the respective piston rod carries a piston 17 which may be of any suitable construction and therefore needs no special description.

Carried by each cylinder at the rookable end thereof is a valve block 18 containing check valves 19, 20 and provided with heads 21, 22 at opposite ends, the head 22 of one of the cylinders having a neck 23 by means of which the usual pump hose may be at tached to the pump but which is not shown in the drawings. Each valve bl ck 18 has a side neck 24 and the two side necks are connected by hose 25 permitting the valve blocks to rock with respect to each other, even though connected by the hose 25.

In the operation of the pump and assuming that the parts are in the position shown in Fig. 1, a movement of the handle 6 toward the left causes air within the right hand cylinder to be forced into the valve block 18 of said cylinder through the valve 19 into the neck or. nipple 24 and into the pipe 25, but as the valve 19 of the other valve block 18 closes to passage of air through the pipe 25 from the first-named cylinder the only escape of the air is through the nipple 23 which is assumed to be connected to the automobile tire. As the movement of the handle 6 continues toward PATENT orr ca.

der rises therein, drawing air through the valve 20 belonging to such cylinder. The right hand piston, because of the toggle relation of the operating lever to the cylinder, moves rapidly at first and then more slowly as the lever 5 and piston rod 12 of the right hand cylinder approach alinement. The result is that great power is exerted upon the right hand piston as the resistance to the movement of the piston increases. At the same time, the left hand piston, having only the work of drawing the air into the cylinder to do, moves more rapidly toward the completion of its stroke than at the beginning. As soon as the handle 6 has been moved to the limitof its travel toward the left it is moved in the opposite direction when the operations described take place in reverse order. In this way the operator has to but operate the lever 5, causing the pump cylinders to work successively but in opposite directions, so that the pumping action is substantially continuous.

The pump units being of the rec1proca-' cal exertion required in pumping actually decreases as the load increases during the power stroke.

Vhat is claimed is A double acting air pump for automobile tires and like purposes, comprising a frame of substantially triangular contour with an extended base, a pair of cylinders each pivoted at the lower end to a corresponding end portion of the basic portion I of the frame in spaced relation to and inclined toward each other within the margins of the sides of the frame, a piston and piston rod for each cylinder with the piston rods rising at an angle toward each other and pivoted together at their upper ends within the margins of the frame, a socket common to the outer ends of both piston rods and to which they are pivoted, a hand lever pivoted to the apex of the triangular frame and having a short arniwithin the margins of the frame entering the socket and a long arm above the frame terminating in a hand hold, an inlet, and outlet valve structure for each cylinder fast thereto at the pivoted end of each cylinder, a hose nipple carried by one valve structure for receiving a pump hose, and a flexible hose connecting the two valve structures and participating in the rocking movements of the valve structures caused by corresponding rockingmovements ofthe cylinders under the action of the pump handle.

In testimony, that I claim the foregoing as my own, I have hereto afiixed my signature.

HORACE LEE FROST. 

